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1.
Plant Physiol ; 191(1): 528-541, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36308454

RESUMEN

Dietary deficiencies of iron and zinc cause human malnutrition that can be mitigated by biofortified staple crops. Conventional breeding approaches to increase grain mineral concentrations in wheat (Triticum aestivum L.) have had only limited success, and our understanding of the genetic and physiological barriers to altering this trait is incomplete. Here we demonstrate that a transgenic approach combining endosperm-specific expression of the wheat VACUOLAR IRON TRANSPORTER gene TaVIT2-D with constitutive expression of the rice (Oryza sativa) NICOTIANAMINE SYNTHASE gene OsNAS2 significantly increases the total concentration of zinc and relocates iron to white-flour fractions. In two distinct bread wheat cultivars, we show that the so called VIT-NAS construct led to a two-fold increase in zinc in wholemeal flour, to ∼50 µg g-1. Total iron was not significantly increased, but redistribution within the grain resulted in a three-fold increase in iron in highly pure, roller-milled white flour, to ∼25 µg g-1. Interestingly, expression of OsNAS2 partially restored iron translocation to the aleurone, which is iron depleted in grain overexpressing TaVIT2 alone. A greater than three-fold increase in the level of the natural plant metal chelator nicotianamine in the grain of VIT-NAS lines corresponded with improved iron and zinc bioaccessibility in white flour. The growth of VIT-NAS plants in the greenhouse was indistinguishable from untransformed controls. Our results provide insights into mineral translocation and distribution in wheat grain and demonstrate that the individual and combined effects of the two transgenes can enhance the nutritional quality of wheat beyond what is possible by conventional breeding.


Asunto(s)
Harina , Zinc , Humanos , Zinc/metabolismo , Harina/análisis , Triticum/genética , Triticum/metabolismo , Fitomejoramiento , Minerales , Grano Comestible/genética , Grano Comestible/metabolismo
2.
Molecules ; 28(10)2023 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-37241825

RESUMEN

Iron is an essential element involved in a variety of physiological functions. However, excess iron catalyzes the generation of reactive oxygen species (ROS) via the Fenton reaction. Oxidative stress, caused by an increase in intracellular ROS production, can be a contributory factor to metabolic syndromes such as dyslipidemia, hypertension, and type 2 diabetes (T2D). Accordingly, interest has grown recently in the role and use of natural antioxidants to prevent iron-induced oxidative damage. This study investigated the protective effect of the phenolic acids; ferulic acid (FA) and its metabolite ferulic acid 4-O-sulfate disodium salt (FAS) against excess iron-related oxidative stress in murine MIN6 cells and the pancreas of BALB/c mice. Rapid iron overload was induced with 50 µmol/L ferric ammonium citrate (FAC) and 20 µmol/L 8-hydroxyquinoline (8HQ) in MIN6 cells, while iron dextran (ID) was used to facilitate iron overload in mice. Cell viability was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay, ROS levels were determined by dihydrodichlorofluorescein (H2DCF) cell-permeant probe, iron levels were measured by inductively coupled plasma mass spectrometry (ICP-MS), glutathione, SOD (superoxide dismutase) and lipid peroxidation, and mRNA were assayed with commercially available kits. The phenolic acids enhanced cell viability in iron-overloaded MIN6 cells in a dose-dependent manner. Furthermore, MIN6 cells exposed to iron showed elevated levels of ROS, glutathione (GSH) depletion and lipid peroxidation (p < 0.05) compared to cells that were protected by treatment with FA or FAS. The treatment of BALB/c mice with FA or FAS following exposure to ID increased the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) gene levels in the pancreas. Consequently, levels of its downstream antioxidant genes, HO-1, NQO1, GCLC and GPX4, increased in the pancreas. In conclusion, this study shows that FA and FAS protect pancreatic cells and liver tissue from iron-induced damage via the Nrf2 antioxidant activation mechanism.


Asunto(s)
Diabetes Mellitus Tipo 2 , Sobrecarga de Hierro , Ratones , Animales , Antioxidantes/farmacología , Antioxidantes/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Hierro/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal , Diabetes Mellitus Tipo 2/metabolismo , Estrés Oxidativo , Glutatión/metabolismo , Sobrecarga de Hierro/metabolismo , Páncreas/metabolismo
3.
Biochem Biophys Res Commun ; 626: 1-7, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-35963044

RESUMEN

Zinc stimulates intestinal iron absorption via induction of divalent metal ion transporter (DMT1) and hephaestin (HEPH). While the increase in DMT1 is mediated via a PI3K/IPR2 axis, the mechanisms of Zn-induced HEPH expression downstream of PI3K remain elusive. In the current study we probed the role of Caudal-related homeobox transcription factor-2 (CDX2) on Zn-induced HEPH expression. Zn treatment of Caco-2 cells increased CDX2 phosphorylation and HEPH protein and mRNA expression. siRNA-silencing of CDX2 inhibited Zn-induced HEPH expression. LY294002, an antagonist of PI3K inhibited Zn-induced phosphorylation of CDX2, and downstream HEPH expression. These results suggest that increased expression of HEPH in intestinal cells following Zn treatment is mediated via a PI3K-CDX2 pathway.


Asunto(s)
Proteínas de la Membrana/metabolismo , Fosfatidilinositol 3-Quinasas , Zinc , Factor de Transcripción CDX2 , Células CACO-2 , Humanos , Hierro/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Zinc/farmacología
4.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36555529

RESUMEN

Ferroptosis is a regulated cell death process characterised by the iron-dependent accumulation of oxidised polyunsaturated fatty acid-containing phospholipids. Its initiation is complicated and involves reactive oxygen species (ROS) and a loss of the activity of the lipid repair enzyme glutathione peroxidase 4 (GPX4). These play critical roles in the development of ferroptotic cell damage by lipid peroxidation. Antioxidant therapy is a promising therapeutic strategy to prevent or even reverse the progression of ferroptosis. This study was designed to demonstrate the protective effect of ferulic acid (FA) against oxidative stress and erastin-mediated ferroptosis in murine MIN6 cells. Cells were treated with FA or its metabolite ferulic acid 4-O-sulfate disodium salt (FAS) and 20 µM of erastin. Cell viability was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay, iron levels were measured by inductively coupled plasma mass spectrometry (ICP-MS), ROS levels were determined by a dihydrodichlorofluorescein (H2DCF) cell-permeant probe, and glutathione and lipid peroxidation were assayed with commercially available kits. The phenolic acids enhanced cell viability in erastin-treated MIN6 cells in a dose-dependent manner. Furthermore, MIN6 cells exposed to erastin alone showed elevated levels of iron and ROS, glutathione (GSH) depletion, and lipid peroxidation (p < 0.05) compared to cells that were protected by co-treatment with FA or FAS. The treatment of MIN6 cells with FA or FAS following exposure to erastin increased the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) protein levels. Consequently, levels of its downstream antioxidant proteins, HO-1, NQO1, GCLC, and GPX4, increased. FA and FAS greatly decreased erastin-induced ferroptosis in the presence of the Nrf2 inhibitor, ML385, through the regulation of Nrf2 response genes. In conclusion, these results show that FA and FAS protect MIN6 cells from erastin-induced ferroptosis by the Nrf2 antioxidant protective mechanism.


Asunto(s)
Ferroptosis , Factor 2 Relacionado con NF-E2 , Animales , Ratones , Antioxidantes/farmacología , Glutatión/metabolismo , Hierro/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba
5.
FASEB J ; 34(8): 9995-10010, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32564472

RESUMEN

Tea polyphenolics have been suggested to possess blood glucose lowering properties by inhibiting sugar transporters in the small intestine and improving insulin sensitivity. In this report, we studied the effects of teas and tea catechins on the small intestinal sugar transporters, SGLT1 and GLUTs (GLUT1, 2 and 5). Green tea extract (GT), oolong tea extract (OT), and black tea extract (BT) inhibited glucose uptake into the intestinal Caco-2 cells with GT being the most potent inhibitor (IC50 : 0.077 mg/mL), followed by OT (IC50 : 0.136 mg/mL) and BT (IC50 : 0.56 mg/mL). GT and OT inhibition of glucose uptake was partial non-competitive, with an inhibitor constant (Ki ) = 0.0317 and 0.0571 mg/mL, respectively, whereas BT was pure non-competitive, Ki  = 0.36 mg/mL. Oocytes injected to express small intestinal GLUTs were inhibited by teas, but SGLT1 was not. Furthermore, catechins present in teas were the predominant inhibitor of glucose uptake into Caco-2 cells, and gallated catechins the most potent: CG > ECG > EGCG ≥ GCG when compared to the non-gallated catechins (C, EC, GC, and EGC). In Caco-2 cells, individual tea catechins reduced the SGLT1 gene, but not protein expression levels. In contrast, GLUT2 gene and protein expression levels were reduced after 2 hours exposure to catechins but increased after 24 hours. These in vitro studies suggest teas containing catechins may be useful dietary supplements capable of blunting postprandial glycaemia in humans, including those with or at risk to Type 2 diabetes mellitus.


Asunto(s)
Antioxidantes/farmacología , Catequina/farmacología , Neoplasias del Colon/tratamiento farmacológico , Transportador de Glucosa de Tipo 2/antagonistas & inhibidores , Extractos Vegetales/farmacología , Transportador 1 de Sodio-Glucosa/antagonistas & inhibidores , Té/química , Animales , Células CACO-2 , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Femenino , Glucosa/metabolismo , Humanos , Oocitos/efectos de los fármacos , Oocitos/crecimiento & desarrollo , Oocitos/metabolismo , Xenopus laevis
6.
Biochem Biophys Res Commun ; 523(4): 987-992, 2020 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-31973819

RESUMEN

In previous studies we demonstrated that zinc stimulates iron uptake in intestinal Caco-2 cells via Zinc-PI3K-IRP2-DMT1 axis. In the current study we investigated the effect of zinc on basolateral iron release and characterized the associated mechanisms. In Caco-2 cells grown on permeable supports, zinc induced iron transport and expression of DMT1, HEPH mRNA and protein, but not that of FPN1. LY294002, an inhibitor of PI3K, inhibited the zinc-induced iron transport, DMT1, HEPH mRNA and protein expression. In addition, LY294002 also inhibited the basal expression of HEPH and FPN1 resulting in blockade of iron egress from cells. In addition, siRNA-silencing of HEPH led to inhibition of both zinc-induced and basal iron transport. Conversely, TPEN, a chelator of zinc, inhibited iron uptake, DMT1, HEPH and FPN1 mRNA and protein expression. These results suggest that intestinal cell zinc status is a critical determinant of iron absorption and effects are mediated via activation of PI3K. Further, PI3K pathway appears to selectively modulate the expression of iron transporters and iron absorption, therefore this might serve as a therapeutic target in iron overload disorders.


Asunto(s)
Absorción Intestinal , Intestinos/fisiología , Hierro/metabolismo , Proteínas de la Membrana/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Zinc/farmacología , Transporte Biológico/efectos de los fármacos , Células CACO-2 , Cromonas/farmacología , Etilenodiaminas/farmacología , Silenciador del Gen/efectos de los fármacos , Humanos , Intestinos/efectos de los fármacos , Morfolinas/farmacología
7.
Biochem J ; 476(11): 1573-1583, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31092704

RESUMEN

The absorption of iron is influenced by numerous dietary and physiological factors. We have previously demonstrated that zinc treatment of intestinal cells increases iron absorption via induction of the apical membrane iron transporter divalent metal ion transporter-1 (DMT1). To better understand the mechanisms of zinc-induced iron absorption, we have studied the effect of zinc on iron uptake, iron transporter and iron regulatory protein (IRP 1 and 2) expression and the impact of the PI3K pathway in differentiated Caco-2 cells, an intestinal cell culture model. We found that zinc induces DMT1 protein and mRNA expression. Zinc-induced DMT1 expression and iron absorption were inhibited by siRNA silencing of DMT1. Furthermore, zinc treatment led to increased abundance of IRP2 protein in cell lysates and in polysomal fractions, implying its binding to target mRNAs. Zinc treatment induced Akt phosphorylation, indicating the activation of the PI3K pathway. LY294002, a specific inhibitor of PI3K inhibited zinc-induced Akt phosphorylation, iron uptake, DMT1 and IRP2 expression. Furthermore, LY294002 also decreased the basal level of DMT1 mRNA but not protein expression. siRNA silencing of IRP2 led to down-regulation of both basal and zinc-induced DMT1 protein expression, implying possible involvement of post-transcriptional regulatory mechanisms. In agreement with these findings, zinc treatment stabilized DMT1 mRNA levels in actinomycin D-treated cells. Based on these findings, we conclude that zinc-induced iron absorption involves elevation of DMT1 expression by stabilization of its mRNA, by a PI3K/IRP2-dependent mechanism.


Asunto(s)
Proteína 2 Reguladora de Hierro/metabolismo , Hierro/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Factores de Transcripción/metabolismo , Zinc/metabolismo , Células CACO-2 , Cromonas/farmacología , Humanos , Absorción Intestinal/efectos de los fármacos , Absorción Intestinal/genética , Absorción Intestinal/fisiología , Morfolinas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Estabilidad del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Regulación hacia Arriba/efectos de los fármacos , Zinc/farmacología
8.
Food Sci Nutr ; 12(1): 280-291, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38268876

RESUMEN

Yams (Dioscorea species) are an important food resource in Madagascar, where both cultivated winged yam (D. alata) and wild edible yams are consumed. However, there is limited knowledge on the nutrient composition of wild edible yams in Madagascar, and on how they compare with the cultivated winged yam. Therefore, in this study, nine wild edible yam species, one with two subspecies from Madagascar (D. bako, D. buckleyana, D. irodensis, D. maciba, D. orangeana, D. pteropoda, D. sambiranensis subsp. bardotiae and subsp. sambiranensis, D. seriflora, and Dioscorea species Ovy valiha), were analyzed for their nutrient composition, compared with cultivated D. alata. They include 6/6 of the most favored wild edible yam species in Madagascar. New nutrient composition data (protein, carbohydrate/starch, energy, lipid, ß-carotene, and minerals) are presented for these nine wild edible yam species. The results show that they contain comparable levels of lipids and starch to D. alata, but none are better sources of protein than D. alata. The results show that D. irodensis contains a significantly higher ß-carotene content when compared to all other edible yams analyzed, and that D. buckleyana, D. irodensis, and D. sambiranensis subsp. bardotiae have a higher calcium content than cultivated D. alata, while all nine wild edible yam species analyzed contain a higher iron content, compared to cultivated D. alata. The nutrient composition data presented could provide new incentives to conserve wild edible yams and inform on strategies to select Dioscorea species for sustainable cultivation and use, providing opportunities to enhance future food security in Madagascar.

9.
Biochem Biophys Rep ; 35: 101521, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37560439

RESUMEN

Liver as iron storage organ is particularly susceptible to oxidative stress-induced injury from excess iron. Thus, antioxidant therapies are often used to reverse oxidative damage and protect cells and tissues. This study investigated the protective effects of phenolic acids; ferulic acid (FA) and its metabolite, ferulic acid 4-O-sulfate disodium salt (FAS) against oxidative stress under iron overload conditions in mouse and HepG2 cells. Cells were exposed to FA or FAS and then treated with iron-induced oxidative stress complex of 50 µmol/L FAC and 20 µmol/L of 8-hydroxyquinoline 8HQ (8HQ-FAC). Iron dextran was injected intraperitoneally on alternate days for 10 days to induce the iron overload condition in BALB/c mice. The study revealed that the phenolic acids were protective against ROS production, lipid peroxidation and antioxidant depletion in HepG2 cells and liver tissues of BALB/c mice during iron-induced oxidative stress. The protective function of phenolic acids was achieved by the transcriptional activation of nuclear factor erythroid-2-related factor 2 (Nrf2) to regulate antioxidant genes. In conclusion, the study provides evidence that FA has the potential as a therapeutic agent against iron-related diseases such as T2D.

10.
Proc Nutr Soc ; : 1-7, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37395294

RESUMEN

Cereal products provide 50 % of iron and 30 % of zinc in the UK diet. However, despite having high content, the bioavailability of minerals from cereals is low. This review discusses strategies to increase mineral bioavailability from cereal-based foods. Iron and zinc are localised to specific tissue structures within cereals; however, the cell walls of these structures are resistant to digestion in the human gastrointestinal tract and therefore the bioaccessibility of these essential minerals from foods for absorption in the intestine is limited. In addition, minerals are stored in cereals bound to phytate, which is the main dietary inhibitor of mineral absorption. Recent research has focused on ways to enhance mineral bioavailability from cereals. Current strategies include disruption of plant cell walls to increase mineral release (bioaccessibility) during digestion; increasing the mineral:phytate ratio either by increasing the mineral content through conventional breeding and/or agronomic biofortification, or by reducing phytate levels; and genetic biofortification to increase the mineral content in the starchy endosperm, which is used to produce white wheat flour. While much of this work is at an early stage, there is potential for these strategies to lead to the development of cereal-based foods with enhanced nutritional qualities that could address the low mineral status in the UK and globally.

11.
Nutrients ; 15(12)2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37375636

RESUMEN

Increasing numbers of individuals follow plant-based diets. This has sparked interest in the nutritional evaluation of the meat substitute sector. Nutritional understanding of these products is vital as plant-based eating becomes more common. For example, animal products are rich sources of iron and zinc, and plant-based foods could be inadequate in these minerals. The main aim was to analyse the mineral composition and absorption from a range of plant-based meat-free burgers and compare them to a typical beef burger. Total and bioaccessible mineral contents of plant-based burgers and a beef burger were determined using microwave digestion and in vitro simulated gastrointestinal digestion, respectively. Mineral bioavailability was analysed by in vitro simulated gastrointestinal digestion of foods, followed by exposure of Caco-2 cells to the sample digests and assessment of mineral uptake. Mineral quantification for all samples was achieved using inductively coupled ICP-optical emission spectrometry (ICP-OES). The content of minerals varied significantly amongst the burgers. Significantly greater quantities of Fe and Zn were found in the beef burger compared to most meat substitutes. Bioaccessible Fe was significantly higher in the beef compared to most of the plant-based meat alternatives; however, bioavailable Fe of most plant-based burgers was comparable to beef (p > 0.05). Similarly, bioaccessible Zn was significantly (p < 0.001) higher from the beef burger. Moreover, beef was superior regarding bioavailable Zn (p ≤ 0.05-0.0001), with only the mycoprotein burger displaying comparable Zn bioavailability (p > 0.05). Beef is an excellent source of bioaccessible Fe and Zn compared to most plant-based substitutes; however, these plant-based substitutes were superior sources of Ca, Cu, Mg and Mn. The quantity of bioaccessible and absorbable Fe varies dramatically among the meat alternatives. Plant-based burgers have the potential to provide adequate quantities of iron and zinc to those consuming such burgers as part of a varied diet. Thus, guiding consumer choices will depend on the variety of the vegetable constituents and their iron nutritional quality in different burgers.


Asunto(s)
Productos de la Carne , Minerales , Humanos , Animales , Bovinos , Células CACO-2 , Hierro/análisis , Productos de la Carne/análisis , Zinc , Plantas
12.
Nutrients ; 14(4)2022 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-35215434

RESUMEN

Trigonella foenum-graecum L. (fenugreek), a member of the legume family (Fabaceae), is a promising source of bioactive phytochemicals, which explains its traditional use for a variety of metabolic disorders including cancer. The current study aimed to evaluate extracts of fenugreek seeds and sprouts, and some of their constituents, to compare their cytotoxic and antiproliferative activities in MCF-7 breast cancer cells. The extracts were chemically characterised using high-resolution accurate mass liquid chromatography-mass spectrometry to reveal the detection of compounds assigned as flavone C-glycosides including those derived from apigenin and luteolin, in addition to isoflavones. Five different flavones or their glycosides (apigenin, vicenin-2, vitexin, luteolin and orientin) and two isoflavones (daidzein and formononetin) were quantified in the fenugreek extracts. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay using MCF-7 cells treated with fenugreek methanolic extracts showed dose- and time-dependent effects on cell viability. The MCF-7 cancer cells treated with the fenugreek methanolic extracts also displayed increased relative mitochondrial DNA damage as well as suppressed metastasis and proliferation. This study demonstrates the potential anti-cancer effects of fenugreek seeds and sprouts and reveals fenugreek sprouts as an untapped resource for bioactive compounds.


Asunto(s)
Neoplasias de la Mama , Trigonella , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Células MCF-7 , Extractos Vegetales/química , Semillas/química , Trigonella/química
13.
Am J Physiol Cell Physiol ; 300(4): C888-95, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21289291

RESUMEN

Hepcidin negatively regulates systemic iron homeostasis in response to inflammation and elevated serum iron. Conversely, hepcidin expression is diminished in response to hypoxia, oxidative stress, and increased erythropoietic demand, though the molecular intermediates involved are incompletely understood. To address this, we have investigated hypoxic hepcidin regulation in HuH7 hepatoma cells either cultured alone or cocultured with activated THP-1 macrophages. HuH7 hepcidin mRNA expression was determined using quantitative polymerase chain reaction (Q-PCR). Hepcidin promoter activity was measured using luciferase reporter constructs containing a 0.9 kb fragment of the wild-type human hepcidin promoter, and constructs containing mutations in bone morphogenetic protein (BMP)/SMAD4, signal transducer and activator of transcription 3 (STAT3), CCAAT/enhancer-binding protein (C/EBP), and E-box-responsive elements. Hepatic expression of bone morphogenetic proteins BMP2 and BMP6 and the BMP inhibitor noggin was determined using Q-PCR, and the protein expression of hemojuvelin (HJV), pSMAD 1/5/8, and SMAD4 was determined by western blotting. Following exposure to hypoxia or H(2)O(2), hepcidin mRNA expression and promoter activity increased in HuH7 cells monocultures but were decreased in HuH7 cells cocultured with THP-1 macrophages. This repression was attenuated by mutation of the BMP/SMAD4-response element, suggesting that modulation of SMAD signaling mediated the response to hypoxia. No changes in hepatocyte BMP2, BMP6 or noggin mRNA, or protein expression of HJV or pSMAD 1/5/8 were detected. However, treatment with hypoxia caused a marked decrease in nuclear and cytosolic SMAD4 protein and SMAD4 mRNA expression in cocultured HuH7 cells. Together these data indicate that hypoxia represses hepcidin expression through inhibition of BMP/SMAD signaling.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Hipoxia/metabolismo , Transducción de Señal/fisiología , Proteína Smad4/metabolismo , Péptidos Catiónicos Antimicrobianos/genética , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Técnicas de Cocultivo , Medios de Cultivo Condicionados/metabolismo , Hepcidinas , Humanos , Neoplasias Hepáticas/metabolismo , Macrófagos/citología , Macrófagos/metabolismo , Mutación , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo
14.
Food Chem ; 335: 127671, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32745843

RESUMEN

Iron deficiency anaemia (IDA) is a common nutritional disorder worldwide. Sustainable food-based approaches are being advocated to use high and bioavailable dietary iron sources to prevent iron deficiency. The study investigated the bioaccessibility and bioavailability of iron from some plant products. Total iron levels in the samples were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). Fractionation of the iron from the digested extracts was carried out by centrifugation and ultrafiltration. Iron bioavailability was determined using an in vitro simulated peptic-pancreatic digestion, followed by measurement of ferritin in Caco-2 cells. The highest amount of bioaccessible iron was obtained from moringa leaves (9.88% ± 0.45 and 8.44 ± 0.01 mg/100 g), but the highest percentage bioavailability was from baobab fruit pulp (99.7% ± 0.13 and 1.74 ± 0.01 mg/100 g) respectively. All the plant products, except for baobab, significantly inhibited iron uptake from FeSO4 and FAC, with fenugreek sprout being the most inhibitory.


Asunto(s)
Adansonia/química , Hierro de la Dieta/farmacocinética , Moringa/química , Trigonella/química , Disponibilidad Biológica , Células CACO-2 , Digestión , Ferritinas/metabolismo , Frutas/química , Humanos , Extractos Vegetales/química , Extractos Vegetales/farmacocinética , Hojas de la Planta/química
15.
Kidney Int ; 78(7): 660-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20631677

RESUMEN

Erythropoietin is produced by the kidney and stimulates erythropoiesis; however, in chronic renal disease its levels are reduced and patients develop anemia that is treatable with iron and recombinant hormone. The mechanism by which erythropoietin improves iron homeostasis is still unclear, but it may involve suppression of the iron regulatory peptide hepcidin and/or a direct effect on intestinal iron absorption. To investigate these possibilities, we used the well-established 5/6th nephrectomy rat model of chronic renal failure with or without human recombinant erythropoietin treatment. Monolayers of human intestinal Caco-2 cells were also treated with erythropoietin to measure any direct effects of this hormone on intestinal iron transport. Nephrectomy increased hepatic hepcidin expression and decreased intestinal iron absorption; these effects were restored to levels found in sham-operated rats on erythropoietin treatment of the rats with renal failure. In Caco-2 cells, the addition of erythropoietin significantly increased the expression of apical divalent metal transporter 1 (DMT1) and basolateral ferroportin and, consequently, iron transport across the monolayer. Taken together, our results show that erythropoietin not only exerts a powerful inhibitory action on the expression of hepcidin, thus permitting the release of iron from reticuloendothelial macrophages and intestinal enterocytes, but also acts directly on enterocytes to increase iron absorption.


Asunto(s)
Eritropoyetina/farmacología , Absorción Intestinal/efectos de los fármacos , Hierro/metabolismo , Fallo Renal Crónico/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos/genética , Células CACO-2 , Proteínas de Transporte de Catión/genética , Modelos Animales de Enfermedad , Duodeno/metabolismo , Hepcidinas , Humanos , Masculino , Nefrectomía , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Receptores de Eritropoyetina/análisis , Transducción de Señal
16.
Am J Physiol Gastrointest Liver Physiol ; 299(3): G778-83, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20576915

RESUMEN

Hepcidin expression in vivo is regulated in proportion to iron status (i.e., increased by iron loading and decreased in iron deficiency). However, in vitro studies with hepatoma cell lines often show an inverse relationship between iron status and hepcidin expression. Here, we investigated possible molecular mechanisms responsible for the differences in iron sensing between hepatoma cell lines and human primary hepatocytes. RNA was collected from primary human hepatocytes, and HepG2 and HuH7 hepatoma cells were treated with either transferrin-bound and non-transferrin-bound iron. Expression of hepcidin, transferrin receptor 2, HFE, and hemojuvelin were quantified by real-time PCR. Hepcidin expression was increased in primary human hepatocytes following 24-h exposure to holoferric transferrin. In contrast, hepcidin mRNA levels in hepatoma cells were decreased by transferrin. Hepcidin expression was positively correlated with transferrin receptor 2 mRNA levels in primary human hepatocytes. Compared with primary hepatocytes, transferrin receptor 2 expression was significantly lower in hepatoma cell lines; furthermore, there was no correlation between transferrin receptor 2 and hepcidin mRNA levels in either HepG2 or HuH7 cells. Taken together our data suggest that transferrin receptor 2 is a likely candidate to explain the differences in iron sensing between hepatoma cell lines and primary human hepatocytes.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Hepatocitos/metabolismo , Hierro/metabolismo , Receptores de Transferrina/metabolismo , Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/metabolismo , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Hepcidinas , Homeostasis , Humanos , Neoplasias Hepáticas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Int J Vitam Nutr Res ; 80(4-5): 231-42, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21462105

RESUMEN

Iron is an essential trace metal in human metabolism. However, imbalances in iron homeostasis are prevalent worldwide and have detrimental effects on human health. Humans do not have the ability to remove excess iron and therefore iron homeostasis is maintained by regulating the amount of iron entering the body from the diet. Iron is present in the human diet in number of different forms, including heme (from meat) and a variety of non-heme iron compounds. While heme is absorbed intact, the bioavailability of non-heme iron varies greatly depending on dietary composition. A number of dietary components are capable of interacting with iron to regulate its solubility and oxidation state. Interestingly, there is an emerging body of evidence suggesting that some nutrients also have direct effects on the expression and function of enterocyte iron transporters. In addition to dietary factors, body iron status is a major determinant of iron absorption. The roles of these important dietary and systemic factors in regulating iron absorption will be discussed in this review.


Asunto(s)
Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Dieta , Absorción Intestinal/genética , Absorción Intestinal/fisiología , Hierro de la Dieta/farmacocinética , Adipoquinas/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos/metabolismo , Disponibilidad Biológica , Citocinas/metabolismo , Eritropoyetina/metabolismo , Hepcidinas , Humanos , Hierro de la Dieta/metabolismo , Estado Nutricional
18.
Sci Rep ; 10(1): 21926, 2020 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-33318518

RESUMEN

Liver iron excess is observed in several chronic liver diseases and is associated with the development of hepatocellular carcinoma (HCC). However, apart from oxidative stress, other cellular mechanisms by which excess iron may mediate/increase HCC predisposition/progression are not known. HCC pathology involves epithelial to mesenchymal transition (EMT), the basis of cancer phenotype acquisition. Here, the effect of excess iron (holo-transferrin 0-2 g/L for 24 and 48 h) on EMT biomarkers in the liver-derived HepG2 cells was investigated. Holo-transferrin substantially increased intracellular iron. Unexpectedly, mRNA and protein expression of the epithelial marker E-cadherin either remained unaltered or increased. The mRNA and protein levels of metastasis marker N-cadherin and mesenchymal marker vimentin increased significantly. While the mRNA expression of EMT transcription factors SNAI1 and SNAI2 increased and decreased, respectively after 24 h, both factors increased after 48 h. The mRNA expression of TGF-ß (EMT-inducer) showed no significant alterations. In conclusion, data showed direct link between iron and EMT. Iron elevated mesenchymal and metastatic biomarkers in HepG2 cells without concomitant decrement in the epithelial marker E-cadherin and altered the expression of the key EMT-mediating transcription factors. Such studies can help identify molecular targets to devise iron-related adjunctive therapies to ameliorate HCC pathophysiology.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Transición Epitelial-Mesenquimal , Hierro/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Carcinoma Hepatocelular/patología , Células Hep G2 , Humanos , Neoplasias Hepáticas/patología , Metástasis de la Neoplasia
19.
Nutrients ; 12(4)2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32290311

RESUMEN

Iron deficiency is a global epidemic affecting a third of the world's population. Current efforts are focused on investigating sustainable ways to improve the bioavailability of iron in plant-based diets. Incorporating microgreens into the diet of at-risk groups in populations could be a useful tool in the management and prevention of iron deficiency. This study analysed and compared the mineral content and bioavailability of iron from microgreen and mature vegetables. The mineral content of rocket, broccoli and fenugreek microgreens and their mature counterparts was determined using microwave digestion and ICP-OES. Iron solubility and bioavailability from the vegetables were determined by a simulated gastrointestinal in vitro digestion and subsequent measurement of ferritin in Caco-2 cells as a surrogate marker of iron uptake. Iron contents of mature fenugreek and rocket were significantly higher than those of the microgreens. Mature fenugreek and broccoli showed significantly (p < 0.001) higher bioaccessibility and low-molecular-weight iron than found in the microgreens. Moreover, iron uptake by Caco-2 cells was significantly higher only from fenugreek microgreens than the mature vegetable. While all vegetables except broccoli enhanced FeSO4 uptake, the response to ferric ammonium citrate (FAC) was inhibitory apart from the mature rocket. Ascorbic acid significantly enhanced iron uptake from mature fenugreek and rocket. Microgreen fenugreek may be bred for a higher content of enhancers of iron availability as a strategy to improve iron nutrition in the populace.


Asunto(s)
Barbarea/química , Disponibilidad Biológica , Brassica/química , Dieta , Análisis de los Alimentos , Tracto Gastrointestinal/metabolismo , Hierro/análisis , Hierro/metabolismo , Fenómenos Fisiológicos de la Nutrición/inmunología , Trigonella/química , Células CACO-2 , Humanos , Técnicas In Vitro , Absorción Intestinal , Solubilidad
20.
BMJ Open ; 10(11): e039231, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33208325

RESUMEN

INTRODUCTION: Micronutrient deficiencies, commonly referred to as 'hidden hunger', affect more than two billion people worldwide, with zinc and iron-deficiency frequently reported. The aim of this study is to examine the impact of consuming zinc biofortified flour (Zincol-2016) on biochemical and functional measures of status in adolescent girls and children living in a low-resource setting in Pakistan. METHODS AND ANALYSIS: We are conducting a pragmatic, cluster-randomised, double-blind, controlled trial. A total of 482 households have been recruited from two catchment areas approximately 30-40 km distance from Peshawar. Household inclusion criteria are the presence of both an adolescent girl, aged 10-16 years, and a child aged 1-5 years. The study duration is 12 months, divided into two 6-month phases. During phase 1, all households will be provided with locally procured flour from standard varieties of wheat. During phase 2, clusters will be paired, and randomised to either the control or intervention arm of the study. The intervention arm will be provided with zinc biofortified wheat flour, with a target zinc concentration of 40 mg/kg. The control arm will be provided with locally procured wheat flour from standard varieties with an expected zinc concentration of 20 mg/kg. The primary outcome measure is plasma zinc concentration. Secondary outcomes include anthropometric measurements, biomarkers of iron and zinc status, and the presence and duration of respiratory tract infections and diarrhoea. ETHICS AND DISSEMINATION: Ethical approval was granted from the University of Central Lancashire STEMH Ethics Committee (reference number: STEMH 1014) and Khyber Medical University Ethics Committee (DIR/KMU-EB/BZ/000683). The final study methods will be published in peer-reviewed journals, alongside the study outcomes. In addition, findings will be disseminated to the scientific community via conference presentations and abstracts and communicated to the study participants through the village elders at an appropriate community forum. TRIAL REGISTRATION NUMBER: ISRCTN17107812; Pre-results.


Asunto(s)
Biofortificación , Triticum , Adolescente , Anciano , Niño , Preescolar , Femenino , Harina , Humanos , Lactante , Pakistán , Ensayos Clínicos Controlados Aleatorios como Asunto , Zinc
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